Media captionGreen Party leader Natalie Bennett calls for a "society for the common good"

The Green Party of England and Wales has launched its campaign for May's local and European elections.

Leader Natalie Bennett said the party was a serious contender and was putting forward its largest ever number of local council candidates.

Ms Bennett also said she was confident the party would increase its current tally of two MEPs.

The launch took place at the Church House Conference Centre in Westminster, central London.

The European Parliament elections take place on Thursday, 22 May, when elections will also take place for 161 councils in England and 11 brand new councils in Northern Ireland.

'The 99%'

Speaking to the BBC after the campaign launch, Ms Bennett said the party hoped to treble its number of MEPs to six, and would need a swing of just 1.6% to do so.

Even with a small number of representatives in the European Parliament, it is "possible to make a real difference" she continued, "as we have done on issues like bankers' bonuses, on fishing policy, on making Europe more friendly and more social".

The party aims to scrap tuition fees and prescription charges in England and Wales, increase child benefit, and renationalise the railways and energy companies.

These policies would be costed by the 2015 general election, she said, but the party was considering imposing a top rate of income tax of more than 50% on the highest earners.

"We need a society that works for the common good, not just the good of the few, which it does at the moment," Ms Bennett said.

"We need real change in our society. It's working for the 1%, not the 99% of us. We need decent benefits, we need to make the minimum wage a living wage, and we need to insure that privatisation doesn't keep costing us an absolute fortune.

"What we need is for multinational companies, rich individuals, to be paying their taxes, which they're simply not doing at the moment."

Appearing on BBC One's Andrew Marr Show on Sunday, Ms Bennett acknowledged that the Greens were "identified with" campaigns against the extraction of shale gas, or fracking.

It was a "very uncertain industry that may very well not get off the ground", she added, and there is "massive and growing public resistance to it" with her party on the "front line" of protests against fracking.

'Party of fear'

She also criticised the government's immigration policy for "cutting our nose off to spite our face".

"This year, for the first time, the number of foreign students applying to British universities has gone down, and that's a huge cost that has come from our immigration policy."

And she said the Greens aimed to position themselves as the "anti-UKIP party".

"UKIP is the party of fear, saying, 'Be fearful, vote for us,'" she explained.

"We're saying, 'Hope for a better society, a society that works for the common good,' so vote Green for that."

Last week, UK Independence Party leader Nigel Farage said there would be "an earthquake" in politics if he triumphed in the European elections.

Launching his party's manifesto in Sheffield, Mr Farage said: "We want to have, post-EU, a sensible, open immigration policy that says we welcome people, but we have got to control the quantity and the quality of who comes to Britain."